Noise: Single Coils vs Computers

[rjb]

Shielding a single coil pickup will not make it quiet, just quieter, especially around computers and the like... only way I can get a quiet atmosphere to record is with shielded hum canceling pickups. So you need both.

So, is your advise to the OP to replace his pickups with shielded, hum canceling pickups?

How about switching to an analog recording studio?

Later,
-rb

[J M Fahey]

How about switching to an analog recording studio?

Not a bad idea.
I do not play, but have a "Strat" and a "LP" available for customers if they could not bring their own guitars.
I just have to turn off the bench TV (1 meter away) with any single coils (it also gets into my "Rick" test bass), simple as that.
The PC monitor (4 yards away) also gets into singles but is usually bearable with HB , unlessI am testing some fiery high gain amp.
For me it's just a reality of life.
Even though my own guitars are shielded, and I reversed the middle "Strat" pickup, plus I reversed its polarity ((I have a speaker magnetizer so that was easy) but I can not touch the customer's guitars !!!
Meaning, I can give them good advice, but it's their privilege to follow it ... or not.
Mostly not.
So I agree with David that there are ways to improve the situation, but also with big tee that in many cases, for different reasons, they are not used.
Oh well.

[kg]

how about you move the computer?

[KenB]

how about you move the computer?

Simple ... my single coils pick up the computer noise hash from quite a ways away ... 10+ feet ... and on top of that it varies with orientation and position of the guitar. Given the spotty (aka undependable) effectiveness of moving the computer, tearing into walls to route cables and such ... it just isn't a practical solution.

I've spent quite a bit of time trouble shooting the problem, running little diagnostic tests and what not ... and based on that ... and as also validated by David ... I have concluded that shielding will not solve the problem.

IMO the bottom line is that ... my vintage single coils have to go ... so the search is on for noiseless single coils.

Thanks everyone!

KenB

[KenB]

At least I don't have this problem ...
MaYaN guitar recordings Day 3 - Gear, Noise, Kitty - YouTube

Beats me how ya deal with noise of that magnitude!

KenB

[J M Fahey]

Part of the problem is that being a home recording, you are the "do it all" guy, so you play and record.
Couple that that you are recording on a home computer.
If you were recording on a Professional studio, to begin with you would be in the Studio itself, not in the Control room.
The Studio is , by definition, "clean" (interference and noise wise) and any Pro equipment which gets into the Control room is as moiseless and interference free as Technology allows.
Why do I write this?
I'd say keep your original pickups for a future recording, or live use, and maybe get "noiseless" ones (which anyway is relative) for your home situation.
Problem is , the interference is not *electrostatic* (where some grounded foil may help you) but *magnetic*, which is much more difficult to deal with.
What kind of monitor are you using?
Tube or SS?

[Steve Conner]

Just to clarify:

The noise is coming from the computer's CPU box? Not a CRT monitor?

Noise from the CPU box is most likely hash from the power supply, or the DC-DC converters on the motherboard. The current draw through these is modulated by whatever the CPU happens to be doing. The result sounds somewhere between radio static, a dialup modem and R2D2. Moving the mouse around, or dragging windows around the desktop, should modulate the noise noticeably.

Another possibility is a high-pitched whine from the hard disk's spindle motor.

I've had troubles like this in the past, and the analog recording studio is tempting. My ultimate solution, to this and many other problems, was to give up trying to make studio-quality recordings at home.

[KenB]

Yep ... the noise is from the computer itself ... not the flat panel monitor.

Beats me what component(s) in the computer are causing it. Although mostly constant it randomly varies a tad now and then depending on what's going on in that mysterious box. Sometimes the noise will stop completely ... just for an instant ... a second or two ... which seems to be related to the loading of a program, a disk read request or a mouse click.

From what I've read ... when it comes to this kind of thing there seems to be little information available ... and tons of what is available appears to be regurgitated here-say mixed with a simple fact or two ... such as the oft blamed ground loop, light dimmer etc ... which in any case is an entirely different problem. My take is it could be almost anything ... from a drive to the data stream in the cables. All of which I find a little odd as I suspect this problem of computer noise with single coils is a common problem ... as there are lots of hackers like me working out of a spare room jammed with computers and other electronic stuff. I woulda thought a clear explanation and fix would be easy to find ... but it isn't.

KenB

[Steve Conner]

I just gave you the clear explanation. The information you posted there agrees with it too. If the noise stops briefly, that's because power management will sometimes shut the CPU down when it's idle.

Unfortunately I don't know of a clear fix, other than moving your computer into the next room. The current draw of a modern CPU can be nearly 100 amps, fluctuating wildly at audio frequencies, and it all passes through a bunch of inductors on the motherboard, which must radiate a pretty strong magnetic field.

Here's what my spare room used to look like before I replaced it all with a laptop. I used this setup to make tracks that got some airplay on local radio.

FWIW, said laptop makes similar noises if you hold the guitar pickups too close to it.

[J M Fahey]

*LOVE* the window view.

And yes, I think that a Notebook must be less noisemaking.
If anything, because of reduced power consumption and shorter wiring.
Just comparing monitor, keyboard and mouse wiring, we went from , say, 6 feet total to just a few inches. Not bad.

[J M Fahey]

Dear KenB , I'm real slow today.
You do not need to move the computer to other room !!!
*YOU* move, with your guitar and a *long* cable.
Use any modern pedal "off" as a line buffer and you'll drive easily a 25 yard cable if necessary.
Do it at least for the heavy distorted high gain parts.
If necessary make a long headphone extension cable too.

[Steve Conner]

JM, the problem is that you have to be close by the computer to work the controls.

Or maybe not. Most DAW software will let you punch in and out with MIDI messages, so you could use a MIDI footswitch with a long cable. Maybe you can even use your smartphone as a remote nowadays.

The 10 meter headphone extension cord is a very useful gadget. Mine are forever getting stolen.

[J M Fahey]

JM, the problem is that you have to be close by the computer to work the controls.

Yes, I KNOW. Ugh!!
The eternal problem of the guy who records, plays, cleans, brews coffee, repairs , setups, and all other micro Studio chores.
Oh well.
Anyway, *while you actually play* , your hands are busy, so like it or not you set up something and then leave the computer alone, even for 30 seconds.
I guess you can set up everything to your liking and then
a) enroll your GF as "operator" , such as "honey, click HERE when I yell NOW!!!! from the other room" or
b) start recording yourself 30 seconds too early, walk up to that chair into the other room, do your magical thing, come back and edit those 30 seconds off.
c) I leave to our computing geniuses the task of designing a remote on/off footswitch which can be used to start/stop recording.
USB maybe?

[Steve Conner]

Hi JM,

Nowadays I work on these kinds of projects with a friend who is a TV/film sound guy in his day job. It makes life much easier to have one of us working the computer while the other murders an instrument.

To make a simple, cheap footswitch, I'd take the guts of a USB keyboard, and attach a momentary stomp switch to the pair of pins on the controller board that correspond to the spacebar, or the "Enter" key or whatever key triggers punch-in in your favourite DAW. I guess some of them will be configurable.

Then I'd build it into an amp footswitch housing, and use it with a long USB cable.

[KenB]

JM, the problem is that you have to be close by the computer to work the controls.

Or maybe not. Most DAW software will let you punch in and out with MIDI messages, so you could use a MIDI footswitch with a long cable. Maybe you can even use your smartphone as a remote nowadays.

The 10 meter headphone extension cord is a very useful gadget. Mine are forever getting stolen.

Oh yeah ... I need to see my stuff ... these days I use guitar sims ... so need to see the monitor, use the mouse and what not. Would be easier to move the computer ... but like I said ... all the little tests I did involving distance didn't yield much positive/dependable results. OTOH ... there has to be a distance that's far enough ... so I suppose I could try putting the darn thing in the garage and run 50+ feet of cables through the attic! At any rate ... DiMarzio noiseless single coils are on the way ... hope they're an improvement.

KenB